Bisphenol A (BPA) was first synthesized and reported between the 1890s and early 1900s, and has been used in various fields, such as in the inner linings of canned foods, thermal paper for receipts, and plastic housings for electronics, toys, and baby bottles. However, it has been discovered that since bisphenol A is an endocrine-disrupting compound, and since it mimics estrogenic hormones by binding to estrogen receptors in endocrine systems, bisphenol A may cause serious health problems. Diseases caused by bisphenol A representatively include reproductive and developmental disorders in infants and children, neurological diseases, cancers, obesity, diabetes, cardiovascular diseases, etc.
The use of bisphenol A has been prohibited due to its environmental and public health implications, but contamination of rivers and reservoirs has continued due to effluents from wastewater treatment plants or leachates from landfills.
In particular, bisphenol A is known to cause such health problems at very low concentrations (10−10 mol/L to 10−8 mol/L (0.02 ng/mL to 2.28 ng/mL, or ppb)), and thus the risk thereof is much greater. In this regard, the perpetual contamination of water supplies by bisphenol A has become one of the primary concerns of environmental and public health agencies.
Accordingly, the importance of laboratory-based and portable quantitative analysis for detecting bisphenol A contamination has gradually increased. Conventional laboratory-based analyses include gas chromatography with mass spectrometry (GC-MS), high-pressure liquid chromatography (HPLC), and a DNA Y junction sensing method, but these have problems in that they are highly dependent on the stability of antibodies and susceptible to nonspecific binding with analog compounds as well as interference from ionic species. Meanwhile, although conventional electrochemical detection has portability via screen-printed electrodes, it is problematic in that it is vulnerable to interfering species.
As one method for detection of bisphenol A, an aptamer for detecting bisphenol A has been developed. For example, Korean Patent Publication No. 2010-0093205 discloses a kit for detecting bisphenol A, which comprises two aptamers specifically binding to bisphenol A. However, bisphenol A, in which two phenol compounds are structurally linked, has a relatively simple structure, whereas the aptamer for detecting bisphenol A has a complicated two-dimensional structure having a large number of stem-loop structures; therefore, the problem has been raised that the bisphenol A detection sensitivity by the aptamer is low. However, solutions to such problem have not yet been provided.
Accordingly, the present inventors have developed a novel aptamer consisting of 14 nucleotides capable of detecting bisphenol A with higher detection sensitivity, through previous studies.
Under these circumstances, the present inventors have endeavored to develop a small nano-aptamer analyzer which is capable of detecting bisphenol A at a concentration level (<1 ng/mL or ppb) at which bisphenol A is present in the environment using the aptamer and which is capable of detecting bisphenol A in the field due to its portability. As a result, they have developed a portable analyzer capable of detecting bisphenol A using the aptamer, and have confirmed that the analyzer can detect bisphenol A at a level equivalent to the results of laboratory-based quantitative analysis of bisphenol A, thereby completing the present invention.